Basis of Presentation, Principles of Consolidation, and Summary of Significant Accounting Policies - Reconciliation of Cash and Cash Equivalents (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
Dec. 31, 2024 |
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| Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||||
| Cash and cash equivalents | $ 711 | $ 1,015 | $ 1,235 | |
| Restricted cash and restricted cash equivalents (included in segregated cash and investments) | 5,029 | 4,640 | ||
| Total cash, cash equivalents, restricted cash, and restricted cash equivalents | $ 5,740 | $ 5,505 | $ 5,875 | $ 3,924 |
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- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of cash and cash equivalent restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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